Vulkan: Refactor SecondaryCommandBuffers class A strictly cosmetic change to move code into alphabetical order. In working with SecondaryCommandBuffer commands in separate CLs, it can be difficult/annoying to track which commands are already in place as some of them are out-of-order. This change puts the command enums, functions, and processing in alphabetical order to simplify searching and adding new commands. Bug: b/154030403 Change-Id: I6dba4cf48d6f27c056585ac633c694e083b1a263 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2158816 Reviewed-by: Jamie Madill <jmadill@chromium.org> Commit-Queue: Tobin Ehlis <tobine@google.com>